The Thrombus Aspiration during Percutaneous coronary intervention in Acute myocardial infarction Study (TAPAS) has shown that thrombus aspiration improves myocardial perfusion and clinical outcome compared to conventional primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction. Impaired myocardial perfusion due to spontaneous or angioplasty-induced embolization of atherothrombotic material also occurs in patients with Non-ST-elevation myocardial infarction (NSTEMI). The aim of this study is to determine whether thrombus aspiration before stent implantation will result in improved myocardial perfusion in patients with NSTEMI compared to conventional PCI.